The following explanations refer mainly to a system for processing fuel, since the preferred application of the process according to the invention is in this area.
Fuel processing processes are known in which at least part of the liquid fuel to be fed into a combustion engine for work, is first catalytically decomposed under reducing or partly oxidizing conditions. The decomposition of the liquid fuel, preferably into gaseous carbon monoxide and hydrogen, is expected to result in a better combustion that produces less harmful substances in the combustion engine, particularly during idling and at low speeds as well as during cold starting and during the warm-up phase.
The utilization of methanol as fuel proved particularly favorable in this case. For one, this fuel can be prepared relatively easily and at relatively low cost from almost all primary energy sources containing carbon. Furthermore, the methanol decomposition reaction is an endothermic process in which the otherwise lost heat of the exhaust gases from the combustion engine can be used to increase the efficiency. Finally, the reaction gases produced during the methanol decomposition contain a relatively large amount of hydrogen, which burns cleanly and ignites even at very lean fuel to air ratios, which contributes to a desirable reduction of the consumption of the combustion engine, especially at low speeds.
The methanol is decomposed according to the equation EQU CH.sub.3 OH.revreaction.CO+2H.sub.2 ( 1)
The reaction (1) is strongly endothermic and can be carried out at temperatures above 200.degree. C. with the aid of heterogeneous catalysts. The gas mixture obtained (known as synthesis gas) contains approximately 33 vol % CO and 66 vol % H.sub.2.
Another industrially interesting process is methanol steam reforming, which proceeds according to the equation EQU CH.sub.3 OH+H.sub.2 O.revreaction.CO.sub.2 +3H.sub.2 ( 2)
This endothermic reaction can also be regarded as a combination of the methanol decomposition reaction (1) and water gas shift reaction according to the equation EQU CO+H.sub.2 O.revreaction.CO.sub.2 +H.sub.2 ( 3)
Methanol steam reforming is usually catalyzed by the same catalysts as the methanol decomposition.